Cambium Networks PMP 430 Series, User Manual

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Chapter 3: System planning Site planning
Page 3-12
be gained by use of a tool or lock and key, or other means of security, and access is controlled by
the authority responsible for the location. Access must only be gained by persons who have been
instructed about the reasons for the restrictions applied to the location and about any precautions
that must be taken. Examples of permissible restricted access locations are a lockable equipment
room or a lockable cabinet.
ODU wind loading
Ensure that the ODU and the structure on which it is mounted are capable of withstanding the prevalent wind
speeds at a proposed PMP/PTP 450i site. Wind speed statistics are available from national meteorological offices.
The ODU and its mounting bracket are capable of withstanding wind speeds of up to 323 kph (200 mph).
Wind blowing on the ODU will subject the mounting structure to significant lateral force. The magnitude of the
force depends on both wind strength and surface area of the ODU. Wind loading is estimated using the following
formulae:
•
Force (in kilogrammes) = 0.1045aV
2
where:
o
“a” is the surface area in square meters, and
o
“V” is the wind speed in meters per second.
•
Force (in pounds) = 0.0042Av 2 where:
o
“A” is the surface area in square feet, and
o
“v” is the wind speed in miles per hour.
Applying these formulae to the 450 platformat different wind speeds, the resulting wind loadings are shown in
below tables.
Table 45 PMP/PTP 450i wind loading (Newton)
Type of ODU
Max surface area
(square meters)
Wind speed (kilometer per hour)
160
170 180 190 200
Connectorized 0.035 59 66 74 83 92
Directional antenna
– 5.x GHz 0.093 156 176 197 220 243
Integrated 90º sector
antenna -5.x
GHz 0.126 211 238 267 298 330